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New SHARP 450nm 1650mw




trinh hong phuoc

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they will not be like m462, i see mostly range from 455-460nm, M462 can reach 470nm, please note that
 

Miya

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sharp 1.65w is 462nm It's just I think. i will Check it. if the diode is in my hand
M462 It can not reach up to 470 nm. The maximum value is just 463 nm.

sharp 1.65w is 455 ~ 460nm? good! but i hope 465nm :giggle:
because 450nm diode is random wavelength
460nm ocean color is beautiful :love:
 

WizardG

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they will not be like m462, i see mostly range from 455-460nm, M462 can reach 470nm, please note that
A few here have pushed M462 diodes up to 470 nm by feeding them enough current. It requires enough current to put the diode into its foldback region (decreasing output due to excessive current) and will almost certainly result in very short diode life, but it can and has been done.
 

paul1598419

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A few here have pushed M462 diodes up to 470 nm by feeding them enough current. It requires enough current to put the diode into its foldback region (decreasing output due to excessive current) and will almost certainly result in very short diode life, but it can and has been done.
I believe you are confusing the NDB7675 with the M462. It was my understanding that the M462 is fairly stable in its wavelength regardless of drive current.
 

DTR

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Yep the M462 was pretty much dead on 462nm. The NDB7675 was often excessively overdriven to get higher wavelengths where the M462 did not like being overdriven.

I was pretty excited seeing the activity on these as I had some samples that arrived this week. Broke them out and was surprised it is the 405nm with the similar model number. Must have mixed them up so no test on them tonight but I went ahead and did on on the 405 since I had it all set up. Will be up shortly.

I do hope these are higher in wavelength. When I contacted to let them know the mixup and get new ones out asked the number on the can and they said they have SB478L691 on them. Might not be the exact same.
 

trinh hong phuoc

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yes, actually the wavelength has the difference of 5nm, some looks like the nubm08 at 4A, anyway I will batch the overall result from you
 

RedCowboy

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Received a diode in the mail today.

With a clean new G2 lens I get 1800mw @ 1.6a reasonably stable
.........................................1850mw @ 1.8a less stable
.........................................1875mw @ 2.0a but it is not stable like at 1.6a

From testing this one diode I don't see any reason to go past 1.6a

The beam is tighter at the lens than a M-140 likely due to it's emitter geometry and it has less of that typical rectangle and is more square with both G2 and G8 ( LOOKS GOOD )

Looks like half the width of the wide side of m-140, but the spot/bar length over distance catches up with the m-140 at around 7 meters, so divergence is higher than m-140 however because of the smaller starting beam diameter it looks better over just the first couple of meters than the rectangle/ribbon m-140 and has a nicer color/wavelength probably 455nm maybe 460nm estimated.

It is a nice square looking ( Half m-140's wide side ) pretty blue beam within the distance of a room estimated 455nm maybe 460nm and by the time it reaches about 7 meters it's a bar like M-140 almost identical spot/bar at 7 meters

My diode has the numbers SB478JN91

64107
 
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DTR

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Ohh.... that hard drop off of efficiency right after the max current raring is not what I would expect. I would like to see some numbers with 1.4A and 1.2A and if the curve starts this drop off between the nominal and max rated current I would say these do no go with the datasheet provided. Maybe a 1W 450 and with the current some of the observations are done at is due to heat buildup in the diode casing some shift.
 

paul1598419

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That is the pinout I would expect with this diode. Your earlier post of it looked wrong to me.
 

RedCowboy

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Yea I just did a quick test, it was happy at 1.2 and well over a watt so I went to 1.6 then saw it didn't really want much more, could just be this one diode, it's the 1st I ordered and just arrived.

I will do another run up after dinner.

Paul, if you put the square notch towards yourself then the right hand pin is positive.

In my earlier post I had it drawn wrong but I had also asked if it was drawn correct or not in the post, I believe my sellers datasheet had it wrong, this is correct below.

64129
 
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paul1598419

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Yeah, those diagrams are usually taken from the top of the diode, so it is likely not backwards.
 
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logsquared

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You know what, the Sharp GH0637AA2G 700nW 638nm diode drops off after the rated current. Maybe Sharp rates their diodes differently?
 

RedCowboy

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The data projector diodes have a fair amount of headroom so the machine can increase current to compensate and make up brightness as it accumulates hours, likely as it gets warm too, they are really robust and I remember when they used to fail if pushed too far, now they bounce back, but I bet this sharp will pop and go LED like the early projector diodes would.
 
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DTR

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The sharp 700mW 638nm is on my list to do testing on but it is a good question. I will push it up to the top and try to do that one tonight.
 




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